An additional two individuals are now in custody related to a theft at Heathrow Airport in which 21 people sustained injuries by what is thought to be an irritant spray, according to law enforcement.
A man, 24, was taken into custody in the Lambeth area on suspicion of robbery and assault and a woman, 23 was arrested on suspicion of conspiracy to commit robbery. Both individuals remain in custody, the force said.
The arrests follow a probe into an attack at the multi-storey car park at Terminal 3 on Sunday. Before the attack, a pair of female travelers had stolen from them their suitcases after getting out of a car park lift.
A toddler aged three was among the those hurt in the event. A total of five individuals went to hospital for treatment and have since been released.
Officers detained a 31-year-old man for suspected theft and assault close to the scene. He was subsequently released under investigation while inquiries continue.
Police were alerted at about 08:10 GMT after reports came in regarding a number of individuals hurt by a noxious substance believed to be pepper spray.
The assault - an event that police said was isolated and not considered terrorism - caused train delays and the temporary shutdown of the main airport tunnel and the T3 car park for a short time.
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